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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
T. F. Heenan, C. R. Adkins
Nuclear Science and Engineering | Volume 45 | Number 3 | September 1971 | Pages 279-296
Technical Paper | doi.org/10.13182/NSE71-A19080
Articles are hosted by Taylor and Francis Online.
A method is presented for calculating pointwise average cross sections in the unresolved region. This method can assess the effects of interference and overlap up to the fourth decimal place in cross-section calculations, having the capability of considering the effects of interference among sequences of resonances and of overlap between resonances in a sequence up to third order in each. Thus, the method, while more sophisticated than justified in view of current cross-section data uncertainties, can be used to evaluate the validity of various approximations currently made in the determination of cross sections for use in Doppler calculations. The effects of the level of approximation on cross-section calculations are given, Hwang's method for calculating the overlap in a single sequence is assessed, and the range of validity of Hwang's method and the approximations used in it are evaluated. Results of studies to determine the relative speed and accuracy of methods for calculating the J integral, performing the statistical average, and computing the complex probability integral, W, are also presented. The effects of interference among sequences are shown to be small for the calculation of cross sections and the Doppler change in cross sections over a wide range of composition. The effects of resonance overlap within one sequence, however, may be significant for the calculation of both cross sections and Doppler changes in cross sections in some critical assemblies.